Circular saw



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ATroRNEYs 1,619, March 1,1927. r Fw ADLOF 78o CIRCULAR SAW Filed Feb.19.192s 2 sheets-sheets il I I v INVENTO fwd@ ATTORN EYS f Patented Mar. 1,1927.

FREDERICK ADLOF, NEW' BRIGHTON, PENNSYLVANIA.

CIRCULAR SAW.

Application led February 19, 1926. Serial No. 89,396.

The tool of the present invention is in the nature of a manuallyoperated disc saw `which is capable of a wide range of utility, butwhich is peculiarly suited for cutting out sections of flooring,partitions, ceilings etc., for the purpose of installing electricalwiring, piping connections or similar appakrat-us.

An object of the invention is to provide a tool for cutting out smallersectionsof flooring or the like with expedition, and in such a mannerthat the wooden floors or partit-ions arenotseriously damaged by thesawing operation. l

Further objects of the invent-ion are to 'provide a tool of this generalcharacter which may be conveniently manipulated even in relativelyinaccessible corners, a toolof simple, practical construction which willbe rugged and durable in use, and vwhich may be manufactured withcomparative economy.

Vith the above noted and other objects in View, the invention consistsin certain novel features of construction and combinations andarrangements of parte, as will be more fully hereinafter set forth andpointed out in the claims. The invention Vmay be more fully understoodfrom the following description in connection with the accompanyingdrawings, wherein- Fig. 1 is a view in side elevation of a toolembodying the invention, showing the device in operative relationship toa floor to be worked upon.

Fig. 2 kis a longitudinal sec-tional view through the tool on the line 22 of F ig. 1.

Fig. 8 is a transverse sectional View on the line 8-3 of Fig. 2.

Fig. 4 is a transverse sectional view on the staggered line 4-4 of Fig.2.

In the drawings I have used the reference characters 10, 10 to designatea pair of vertical guiding uprights rising from a base plate 11, Spursor teeth 12 on the under face of the base plate are adapted to engage ina floor or partition 13 to prevent slipping of the frame when startingoperation of the tool. The cross sectional shape of the uprights may bebest seen in Fig. 4. wherein it will be noted that they include opposedfiat faces and bevelled side faces. A carriage 14 vertically slidable inthe grueling standards 10 is grooved at 15 to fit the standards. Thecarriage 14 is preferably formed of a pair of complementary blocks 14and 14". Block 7.4* preferably carries the operating mechanism for thedisc saw 16 carried by the block 14h. sions 17 passed through openings18 in the block 14h, and set screws 19 are used to retain the two blocksin assembled relationship.

Means is provided for normally holding the carriage 14 in elevatedposition to retain the saw 16 out of contact with the supporting surface18 upon which the base plate 11 of the frame rests. @ne simple mechanismfor accomplishing this result has been indicated, and includes a guiderod 20 having bearings in the transverse head 21 of the carriage guideland frame, and in a cap 22 screwed on to a vertical tubularspringhousingl 23 which is mounted on the member 21. A coiled expansion spring24 disposed within the housing, encircles the guide rod-20, bears at oneendagainst the member 21, and at its other endy against a collar 85 onthe rod.V This spring tends to retain the carriage 14 in elevatedposition, and a handle 26 on the upper end of the r0d20 is provided foreffecting manual depression of the carriage against ythe act-ion of thespring, thereby moving the saw intoV engagement with the work. VAnadditional stationary handle member `2.7' is. also provided on thetubular spring housing 28, and when the carriage has been manuallydepressed for a i short distance, the handle 26 will approach closeenough to the handle 27 Vfor the operator to grasp both handles with onehand, for a purpose to be later described.

Obviously the mechanism for manually driving the disc saw 16 is subjectto considerable variation, but I have shown one convenient form ofmechanism which in'- cludes a. driving gear 28 journalled on a stud 29which projects from Vthe face of the block 14a. An operating crank arm30 for the gear wheel 28 carries a handle 31 which may be manuallygrasped and turned. Below the gear wheel 28 andv meshing therewith is aspeed increasing gear 32 journalled on ak stud 33. Gear 32 meshes with apinion 84 on one end of a transverse shaft 35 extending through thelower end of the carriage and bearing at its opposite end the disc saw16. It will be apparent that relatively slow rotation of the drivinggear 28 will effect rapid rotation of the saw. Preferably the gearwheels 28, 82, 34 are protected by a guard plate 86, the flangedperipheral edges 37 of which project outwardly over Block 14aLpreferably includes eXtenthe gears. The saw 16 is also protected byguard plate 88 of approximately semi-circular shape which is slightlyspaced from the carriage block 14h and defines a housing in which theupper half of the disc saw turns.

The pinion 34 is faced With a disc 34a of larger diameter than thepinion, and the saw 16 is provided with a hub 16, the same diameter asthe disc 34a.

By virtue of this construction. the disc 84" and hub 16a will engage thefloor 13 before the carriage 14 engages the base 12 of the carriageframe. IVhen this occurs, liandles 26 and 2T will be relatively Vclosetogether, and they may be manually grasped to elevate the guide frame10, and lift the teeth 12 out of engagement With the floor, the toolthen resting upn the disc 34a and hub 16a Which Will serve Vas tractionmeans for shifting the tool along the licor and causing the saw to cut anotch of any desired length. Y

I Theoperation of the device Will be evident from the foregoingdescription. Car riage 14a with the saiv and saw operating gears isordinarily retained at the upper end of its guide frame by the spring`24. then the tool is to be used however, the handle 26 affords means for.manually depressing. the carriagell and feeding the saw into the Workat the proper rate which is predetermined by the speed of rotation ofthe manually operated driving gear 28.

The manner in which the tivo handles may be manually grasped todisengage the teeth A 12 from the floor and permit the tool to beshifted along on the disc 34 and hub 16a of the saw, has been previouslydescribed.

Various changes and alterations might be made in the general form andarrangement of parts described without departing naief/so from theinvention. Hence I do not Wish to limit myself to the details set forth,but shall consider myself at liberty to make such `changes andalterations as fairly fall Within gageable with the surface of thematerial to n be sawed, a sau7 carriage slidable in the guide frame.vand normally spring retracted to ietain'tlie saw out of engagement withthe Work, a transverse shaft mounted in the carriage, and a disc sawcarried by the shaft, traction means at the ends of the shaft adapted toengage the surface of the Work before the carriage engages the endof itsguideway, and means permitting retraction of the guide frame todisengage the teeth, whereby the tool may travel on the traction means.

2. It a tool of the class described, a guide frame having teeth at oneend thereof engageable with the surface of the material to be sawed, asaiv carriage slidable in the guide frame, and normally spring retractedto retain the saw out of engagement with the Work, a transverse shaftmounted in the carriage, and a. disc saw carried by the shaft, tractionmeans at the ends of the shaft adapted to engage the surface of the Workbefore the carriage engages the end of its guideivay, andmeanspermitting retraction of vthe guide frame to disengage the.

teeth, whereby the tool may. travel on the Y traction means, said meansincluding Vhandles rigid with the guide frame and with -the carriagerespectively adapted to be maiiually grasped and advanced toward eachother to effect disengagement of the teeth.

FREDERICK IV. ADLOF.

